xref: /btstack/src/hci.c (revision c9af4d3f19c8eb0849d0dbf67148b9c0bf6a3082)
1 /*
2  * Copyright (C) 2009-2012 by Matthias Ringwald
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY MATTHIAS RINGWALD AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
24  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at [email protected]
34  *
35  */
36 
37 /*
38  *  hci.c
39  *
40  *  Created by Matthias Ringwald on 4/29/09.
41  *
42  */
43 
44 #include "config.h"
45 
46 #include "hci.h"
47 
48 #include <stdarg.h>
49 #include <string.h>
50 #include <stdio.h>
51 
52 #ifndef EMBEDDED
53 #include <unistd.h> // gethostbyname
54 #include <btstack/version.h>
55 #endif
56 
57 #include "btstack_memory.h"
58 #include "debug.h"
59 #include "hci_dump.h"
60 
61 #include <btstack/hci_cmds.h>
62 
63 #define HCI_CONNECTION_TIMEOUT_MS 10000
64 
65 #define HCI_INTIALIZING_SUBSTATE_AFTER_SLEEP 11
66 
67 #ifdef USE_BLUETOOL
68 #include "bt_control_iphone.h"
69 #endif
70 
71 static void hci_update_scan_enable(void);
72 
73 // the STACK is here
74 static hci_stack_t       hci_stack;
75 
76 /**
77  * get connection for a given handle
78  *
79  * @return connection OR NULL, if not found
80  */
81 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
82     linked_item_t *it;
83     for (it = (linked_item_t *) hci_stack.connections; it ; it = it->next){
84         if ( ((hci_connection_t *) it)->con_handle == con_handle){
85             return (hci_connection_t *) it;
86         }
87     }
88     return NULL;
89 }
90 
91 static void hci_connection_timeout_handler(timer_source_t *timer){
92     hci_connection_t * connection = (hci_connection_t *) linked_item_get_user(&timer->item);
93 #ifdef HAVE_TIME
94     struct timeval tv;
95     gettimeofday(&tv, NULL);
96     if (tv.tv_sec >= connection->timestamp.tv_sec + HCI_CONNECTION_TIMEOUT_MS/1000) {
97         // connections might be timed out
98         hci_emit_l2cap_check_timeout(connection);
99     }
100 #endif
101 #ifdef HAVE_TICK
102     if (embedded_get_ticks() > connection->timestamp + embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
103         // connections might be timed out
104         hci_emit_l2cap_check_timeout(connection);
105     }
106 #endif
107     run_loop_set_timer(timer, HCI_CONNECTION_TIMEOUT_MS);
108     run_loop_add_timer(timer);
109 }
110 
111 static void hci_connection_timestamp(hci_connection_t *connection){
112 #ifdef HAVE_TIME
113     gettimeofday(&connection->timestamp, NULL);
114 #endif
115 #ifdef HAVE_TICK
116     connection->timestamp = embedded_get_ticks();
117 #endif
118 }
119 
120 /**
121  * create connection for given address
122  *
123  * @return connection OR NULL, if no memory left
124  */
125 static hci_connection_t * create_connection_for_addr(bd_addr_t addr){
126     hci_connection_t * conn = (hci_connection_t *) btstack_memory_hci_connection_get();
127     if (!conn) return NULL;
128     BD_ADDR_COPY(conn->address, addr);
129     conn->con_handle = 0xffff;
130     conn->authentication_flags = AUTH_FLAGS_NONE;
131     linked_item_set_user(&conn->timeout.item, conn);
132     conn->timeout.process = hci_connection_timeout_handler;
133     hci_connection_timestamp(conn);
134     conn->acl_recombination_length = 0;
135     conn->acl_recombination_pos = 0;
136     conn->num_acl_packets_sent = 0;
137     linked_list_add(&hci_stack.connections, (linked_item_t *) conn);
138     return conn;
139 }
140 
141 /**
142  * get connection for given address
143  *
144  * @return connection OR NULL, if not found
145  */
146 static hci_connection_t * connection_for_address(bd_addr_t address){
147     linked_item_t *it;
148     for (it = (linked_item_t *) hci_stack.connections; it ; it = it->next){
149         if ( ! BD_ADDR_CMP( ((hci_connection_t *) it)->address, address) ){
150             return (hci_connection_t *) it;
151         }
152     }
153     return NULL;
154 }
155 
156 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
157     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
158 }
159 
160 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
161     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
162 }
163 
164 
165 /**
166  * add authentication flags and reset timer
167  */
168 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
169     bd_addr_t addr;
170     bt_flip_addr(addr, *(bd_addr_t *) bd_addr);
171     hci_connection_t * conn = connection_for_address(addr);
172     if (conn) {
173         connectionSetAuthenticationFlags(conn, flags);
174         hci_connection_timestamp(conn);
175     }
176 }
177 
178 int  hci_authentication_active_for_handle(hci_con_handle_t handle){
179     hci_connection_t * conn = hci_connection_for_handle(handle);
180     if (!conn) return 0;
181     if (!conn->authentication_flags) return 0;
182     if (conn->authentication_flags & SENT_LINK_KEY_REPLY) return 0;
183     if (conn->authentication_flags & RECV_LINK_KEY_NOTIFICATION) return 0;
184     return 1;
185 }
186 
187 void hci_drop_link_key_for_bd_addr(bd_addr_t *addr){
188     if (hci_stack.remote_device_db) {
189         hci_stack.remote_device_db->delete_link_key(addr);
190     }
191 }
192 
193 
194 /**
195  * count connections
196  */
197 static int nr_hci_connections(void){
198     int count = 0;
199     linked_item_t *it;
200     for (it = (linked_item_t *) hci_stack.connections; it ; it = it->next, count++);
201     return count;
202 }
203 
204 /**
205  * Dummy handler called by HCI
206  */
207 static void dummy_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
208 }
209 
210 uint8_t hci_number_outgoing_packets(hci_con_handle_t handle){
211     hci_connection_t * connection = hci_connection_for_handle(handle);
212     if (!connection) {
213         log_error("hci_number_outgoing_packets connectino for handle %u does not exist!\n", handle);
214         return 0;
215     }
216     return connection->num_acl_packets_sent;
217 }
218 
219 uint8_t hci_number_free_acl_slots(){
220     uint8_t free_slots = hci_stack.total_num_acl_packets;
221     linked_item_t *it;
222     for (it = (linked_item_t *) hci_stack.connections; it ; it = it->next){
223         hci_connection_t * connection = (hci_connection_t *) it;
224         if (free_slots < connection->num_acl_packets_sent) {
225             log_error("hci_number_free_acl_slots: sum of outgoing packets > total acl packets!\n");
226             return 0;
227         }
228         free_slots -= connection->num_acl_packets_sent;
229     }
230     return free_slots;
231 }
232 
233 int hci_can_send_packet_now(uint8_t packet_type){
234 
235     // check for async hci transport implementations
236     if (hci_stack.hci_transport->can_send_packet_now){
237         if (!hci_stack.hci_transport->can_send_packet_now(packet_type)){
238             return 0;
239         }
240     }
241 
242     // check regular Bluetooth flow control
243     switch (packet_type) {
244         case HCI_ACL_DATA_PACKET:
245             return hci_number_free_acl_slots();
246         case HCI_COMMAND_DATA_PACKET:
247             return hci_stack.num_cmd_packets;
248         default:
249             return 0;
250     }
251 }
252 
253 int hci_send_acl_packet(uint8_t *packet, int size){
254 
255     // check for free places on BT module
256     if (!hci_number_free_acl_slots()) return BTSTACK_ACL_BUFFERS_FULL;
257 
258     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
259     hci_connection_t *connection = hci_connection_for_handle( con_handle);
260     if (!connection) return 0;
261     hci_connection_timestamp(connection);
262 
263     // count packet
264     connection->num_acl_packets_sent++;
265     // log_info("hci_send_acl_packet - handle %u, sent %u\n", connection->con_handle, connection->num_acl_packets_sent);
266 
267     // send packet
268     int err = hci_stack.hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
269 
270     return err;
271 }
272 
273 static void acl_handler(uint8_t *packet, int size){
274 
275     // get info
276     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
277     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
278     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
279     uint16_t acl_length         = READ_ACL_LENGTH(packet);
280 
281     // ignore non-registered handle
282     if (!conn){
283         log_error( "hci.c: acl_handler called with non-registered handle %u!\n" , con_handle);
284         return;
285     }
286 
287     // update idle timestamp
288     hci_connection_timestamp(conn);
289 
290     // handle different packet types
291     switch (acl_flags & 0x03) {
292 
293         case 0x01: // continuation fragment
294 
295             // sanity check
296             if (conn->acl_recombination_pos == 0) {
297                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x\n", con_handle);
298                 return;
299             }
300 
301             // append fragment payload (header already stored)
302             memcpy(&conn->acl_recombination_buffer[conn->acl_recombination_pos], &packet[4], acl_length );
303             conn->acl_recombination_pos += acl_length;
304 
305             // log_error( "ACL Cont Fragment: acl_len %u, combined_len %u, l2cap_len %u\n", acl_length,
306             //        conn->acl_recombination_pos, conn->acl_recombination_length);
307 
308             // forward complete L2CAP packet if complete.
309             if (conn->acl_recombination_pos >= conn->acl_recombination_length + 4 + 4){ // pos already incl. ACL header
310 
311                 hci_stack.packet_handler(HCI_ACL_DATA_PACKET, conn->acl_recombination_buffer, conn->acl_recombination_pos);
312                 // reset recombination buffer
313                 conn->acl_recombination_length = 0;
314                 conn->acl_recombination_pos = 0;
315             }
316             break;
317 
318         case 0x02: { // first fragment
319 
320             // sanity check
321             if (conn->acl_recombination_pos) {
322                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x\n", con_handle);
323                 return;
324             }
325 
326             // peek into L2CAP packet!
327             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
328 
329             // log_error( "ACL First Fragment: acl_len %u, l2cap_len %u\n", acl_length, l2cap_length);
330 
331             // compare fragment size to L2CAP packet size
332             if (acl_length >= l2cap_length + 4){
333 
334                 // forward fragment as L2CAP packet
335                 hci_stack.packet_handler(HCI_ACL_DATA_PACKET, packet, acl_length + 4);
336 
337             } else {
338                 // store first fragment and tweak acl length for complete package
339                 memcpy(conn->acl_recombination_buffer, packet, acl_length + 4);
340                 conn->acl_recombination_pos    = acl_length + 4;
341                 conn->acl_recombination_length = l2cap_length;
342                 bt_store_16(conn->acl_recombination_buffer, 2, l2cap_length +4);
343             }
344             break;
345 
346         }
347         default:
348             log_error( "hci.c: acl_handler called with invalid packet boundary flags %u\n", acl_flags & 0x03);
349             return;
350     }
351 
352     // execute main loop
353     hci_run();
354 }
355 
356 static void hci_shutdown_connection(hci_connection_t *conn){
357     log_info("Connection closed: handle %u, %s\n", conn->con_handle, bd_addr_to_str(conn->address));
358 
359     // cancel all l2cap connections
360     hci_emit_disconnection_complete(conn->con_handle, 0x16);    // terminated by local host
361 
362     run_loop_remove_timer(&conn->timeout);
363 
364     linked_list_remove(&hci_stack.connections, (linked_item_t *) conn);
365     btstack_memory_hci_connection_free( conn );
366 
367     // now it's gone
368     hci_emit_nr_connections_changed();
369 }
370 
371 static const uint16_t packet_type_sizes[] = {
372     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
373     HCI_ACL_DH1_SIZE, 0, 0, 0,
374     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
375     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
376 };
377 static const uint8_t  packet_type_feature_requirement_bit[] = {
378      0, // 3 slot packets
379      1, // 5 slot packets
380     25, // EDR 2 mpbs
381     26, // EDR 3 mbps
382     39, // 3 slot EDR packts
383     40, // 5 slot EDR packet
384 };
385 static const uint16_t packet_type_feature_packet_mask[] = {
386     0x0f00, // 3 slot packets
387     0xf000, // 5 slot packets
388     0x1102, // EDR 2 mpbs
389     0x2204, // EDR 3 mbps
390     0x0300, // 3 slot EDR packts
391     0x3000, // 5 slot EDR packet
392 };
393 
394 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
395     // enable packet types based on size
396     uint16_t packet_types = 0;
397     int i;
398     for (i=0;i<16;i++){
399         if (packet_type_sizes[i] == 0) continue;
400         if (packet_type_sizes[i] <= buffer_size){
401             packet_types |= 1 << i;
402         }
403     }
404     // disable packet types due to missing local supported features
405     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
406         int bit_idx = packet_type_feature_requirement_bit[i];
407         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
408         if (feature_set) continue;
409         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
410         packet_types &= ~packet_type_feature_packet_mask[i];
411     }
412     // flip bits for "may not be used"
413     packet_types ^= 0x3306;
414     return packet_types;
415 }
416 
417 uint16_t hci_usable_acl_packet_types(void){
418     return hci_stack.packet_types;
419 }
420 
421 uint8_t* hci_get_outgoing_acl_packet_buffer(void){
422     // hci packet buffer is >= acl data packet length
423     return hci_stack.hci_packet_buffer;
424 }
425 
426 uint16_t hci_max_acl_data_packet_length(void){
427     return hci_stack.acl_data_packet_length;
428 }
429 
430 int hci_ssp_supported(void){
431     // No 51, byte 6, bit 3
432     return (hci_stack.local_supported_features[6] & (1 << 3)) != 0;
433 }
434 
435 int hci_classic_supported(void){
436     // No 37, byte 4, bit 5, = No BR/EDR Support
437     return (hci_stack.local_supported_features[4] & (1 << 5)) == 0;
438 }
439 
440 int hci_le_supported(void){
441     // No 37, byte 4, bit 6 = LE Supported (Controller)
442 #ifdef HAVE_BLE
443     return (hci_stack.local_supported_features[4] & (1 << 6)) != 0;
444 #else
445     return 0;
446 #endif
447 }
448 
449 // avoid huge local variables
450 #ifndef EMBEDDED
451 static device_name_t device_name;
452 #endif
453 static void event_handler(uint8_t *packet, int size){
454     bd_addr_t addr;
455     uint8_t link_type;
456     hci_con_handle_t handle;
457     hci_connection_t * conn;
458     int i;
459 
460     // printf("HCI:EVENT:%02x\n", packet[0]);
461 
462     switch (packet[0]) {
463 
464         case HCI_EVENT_COMMAND_COMPLETE:
465             // get num cmd packets
466             // log_info("HCI_EVENT_COMMAND_COMPLETE cmds old %u - new %u\n", hci_stack.num_cmd_packets, packet[2]);
467             hci_stack.num_cmd_packets = packet[2];
468 
469             if (COMMAND_COMPLETE_EVENT(packet, hci_read_buffer_size)){
470                 // from offset 5
471                 // status
472                 // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
473                 hci_stack.acl_data_packet_length = READ_BT_16(packet, 6);
474                 // ignore: SCO data packet len (8)
475                 hci_stack.total_num_acl_packets  = packet[9];
476                 // ignore: total num SCO packets
477                 if (hci_stack.state == HCI_STATE_INITIALIZING){
478                     // determine usable ACL payload size
479                     if (HCI_ACL_PAYLOAD_SIZE < hci_stack.acl_data_packet_length){
480                         hci_stack.acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
481                     }
482                     log_info("hci_read_buffer_size: used size %u, count %u\n",
483                              hci_stack.acl_data_packet_length, hci_stack.total_num_acl_packets);
484                 }
485             }
486 #ifdef HAVE_BLE
487             if (COMMAND_COMPLETE_EVENT(packet, hci_le_read_buffer_size)){
488                 hci_stack.le_data_packet_length = READ_BT_16(packet, 6);
489                 hci_stack.total_num_le_packets  = packet[8];
490                 log_info("hci_le_read_buffer_size: size %u, count %u\n", hci_stack.le_data_packet_length, hci_stack.total_num_le_packets);
491             }
492 #endif
493             // Dump local address
494             if (COMMAND_COMPLETE_EVENT(packet, hci_read_bd_addr)) {
495                 bt_flip_addr(hci_stack.local_bd_addr, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1]);
496                 log_info("Local Address, Status: 0x%02x: Addr: %s\n",
497                     packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE], bd_addr_to_str(hci_stack.local_bd_addr));
498             }
499             if (COMMAND_COMPLETE_EVENT(packet, hci_write_scan_enable)){
500                 hci_emit_discoverable_enabled(hci_stack.discoverable);
501             }
502             // Note: HCI init checks
503             if (COMMAND_COMPLETE_EVENT(packet, hci_read_local_supported_features)){
504                 memcpy(hci_stack.local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 8);
505                 log_info("Local Supported Features: 0x%02x%02x%02x%02x%02x%02x%02x%02x",
506                     hci_stack.local_supported_features[0], hci_stack.local_supported_features[1],
507                     hci_stack.local_supported_features[2], hci_stack.local_supported_features[3],
508                     hci_stack.local_supported_features[4], hci_stack.local_supported_features[5],
509                     hci_stack.local_supported_features[6], hci_stack.local_supported_features[7]);
510 
511                 // determine usable ACL packet types based buffer size and supported features
512                 hci_stack.packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(hci_stack.acl_data_packet_length, &hci_stack.local_supported_features[0]);
513                 log_info("packet types %04x", hci_stack.packet_types);
514 
515                 // Classic/LE
516                 log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
517             }
518             break;
519 
520         case HCI_EVENT_COMMAND_STATUS:
521             // get num cmd packets
522             // log_info("HCI_EVENT_COMMAND_STATUS cmds - old %u - new %u\n", hci_stack.num_cmd_packets, packet[3]);
523             hci_stack.num_cmd_packets = packet[3];
524             break;
525 
526         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:
527             for (i=0; i<packet[2];i++){
528                 handle = READ_BT_16(packet, 3 + 2*i);
529                 uint16_t num_packets = READ_BT_16(packet, 3 + packet[2]*2 + 2*i);
530                 conn = hci_connection_for_handle(handle);
531                 if (!conn){
532                     log_error("hci_number_completed_packet lists unused con handle %u\n", handle);
533                     continue;
534                 }
535                 conn->num_acl_packets_sent -= num_packets;
536                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u\n", num_packets, handle, conn->num_acl_packets_sent);
537             }
538             break;
539 
540         case HCI_EVENT_CONNECTION_REQUEST:
541             bt_flip_addr(addr, &packet[2]);
542             // TODO: eval COD 8-10
543             link_type = packet[11];
544             log_info("Connection_incoming: %s, type %u\n", bd_addr_to_str(addr), link_type);
545             if (link_type == 1) { // ACL
546                 conn = connection_for_address(addr);
547                 if (!conn) {
548                     conn = create_connection_for_addr(addr);
549                 }
550                 if (!conn) {
551                     // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
552                     hci_stack.decline_reason = 0x0d;
553                     BD_ADDR_COPY(hci_stack.decline_addr, addr);
554                     break;
555                 }
556                 conn->state = RECEIVED_CONNECTION_REQUEST;
557                 hci_run();
558             } else {
559                 // SYNCHRONOUS CONNECTION LIMIT TO A DEVICE EXCEEDED (0X0A)
560                 hci_stack.decline_reason = 0x0a;
561                 BD_ADDR_COPY(hci_stack.decline_addr, addr);
562             }
563             break;
564 
565         case HCI_EVENT_CONNECTION_COMPLETE:
566             // Connection management
567             bt_flip_addr(addr, &packet[5]);
568             log_info("Connection_complete (status=%u) %s\n", packet[2], bd_addr_to_str(addr));
569             conn = connection_for_address(addr);
570             if (conn) {
571                 if (!packet[2]){
572                     conn->state = OPEN;
573                     conn->con_handle = READ_BT_16(packet, 3);
574 
575                     // restart timer
576                     run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
577                     run_loop_add_timer(&conn->timeout);
578 
579                     log_info("New connection: handle %u, %s\n", conn->con_handle, bd_addr_to_str(conn->address));
580 
581                     hci_emit_nr_connections_changed();
582                 } else {
583                     // connection failed, remove entry
584                     linked_list_remove(&hci_stack.connections, (linked_item_t *) conn);
585                     btstack_memory_hci_connection_free( conn );
586 
587                     // if authentication error, also delete link key
588                     if (packet[2] == 0x05) {
589                         hci_drop_link_key_for_bd_addr(&addr);
590                     }
591                 }
592             }
593             break;
594 
595         case HCI_EVENT_LINK_KEY_REQUEST:
596             log_info("HCI_EVENT_LINK_KEY_REQUEST\n");
597             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
598             if (!hci_stack.remote_device_db) break;
599             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
600             hci_run();
601             // request handled by hci_run() as HANDLE_LINK_KEY_REQUEST gets set
602             return;
603 
604         case HCI_EVENT_LINK_KEY_NOTIFICATION:
605             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_NOTIFICATION);
606             if (!hci_stack.remote_device_db) break;
607             bt_flip_addr(addr, &packet[2]);
608             hci_stack.remote_device_db->put_link_key(&addr, (link_key_t *) &packet[8]);
609             // still forward event to allow dismiss of pairing dialog
610             break;
611 
612         case HCI_EVENT_PIN_CODE_REQUEST:
613             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_PIN_CODE_REQUEST);
614             // PIN CODE REQUEST means the link key request didn't succee -> delete stored link key
615             if (!hci_stack.remote_device_db) break;
616             bt_flip_addr(addr, &packet[2]);
617             hci_stack.remote_device_db->delete_link_key(&addr);
618             break;
619 
620         case HCI_EVENT_IO_CAPABILITY_REQUEST:
621             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
622             if (hci_stack.ssp_io_capability == SSP_IO_CAPABILITY_UNKNOWN) break;
623             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_REPLY);
624             break;
625 
626         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
627             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_USER_CONFIRM_REQUEST);
628             if (!hci_stack.ssp_auto_accept) break;
629             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_CONFIRM_REPLY);
630             break;
631 
632         case HCI_EVENT_USER_PASSKEY_REQUEST:
633             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_USER_PASSKEY_REQUEST);
634             if (!hci_stack.ssp_auto_accept) break;
635             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_PASSKEY_REPLY);
636             break;
637 
638 #ifndef EMBEDDED
639         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
640             if (!hci_stack.remote_device_db) break;
641             if (packet[2]) break; // status not ok
642             bt_flip_addr(addr, &packet[3]);
643             // fix for invalid remote names - terminate on 0xff
644             for (i=0; i<248;i++){
645                 if (packet[9+i] == 0xff){
646                     packet[9+i] = 0;
647                     break;
648                 }
649             }
650             memset(&device_name, 0, sizeof(device_name_t));
651             strncpy((char*) device_name, (char*) &packet[9], 248);
652             hci_stack.remote_device_db->put_name(&addr, &device_name);
653             break;
654 
655         case HCI_EVENT_INQUIRY_RESULT:
656         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
657             if (!hci_stack.remote_device_db) break;
658             // first send inq result packet
659             hci_stack.packet_handler(HCI_EVENT_PACKET, packet, size);
660             // then send cached remote names
661             for (i=0; i<packet[2];i++){
662                 bt_flip_addr(addr, &packet[3+i*6]);
663                 if (hci_stack.remote_device_db->get_name(&addr, &device_name)){
664                     hci_emit_remote_name_cached(&addr, &device_name);
665                 }
666             }
667             return;
668 #endif
669 
670         case HCI_EVENT_DISCONNECTION_COMPLETE:
671             if (!packet[2]){
672                 handle = READ_BT_16(packet, 3);
673                 hci_connection_t * conn = hci_connection_for_handle(handle);
674                 if (conn) {
675                     hci_shutdown_connection(conn);
676                 }
677             }
678             break;
679 
680         case HCI_EVENT_HARDWARE_ERROR:
681             if(hci_stack.control->hw_error){
682                 (*hci_stack.control->hw_error)();
683             }
684             break;
685 
686 #ifdef HAVE_BLE
687         case HCI_EVENT_LE_META:
688             switch (packet[2]) {
689                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
690                     // Connection management
691                     bt_flip_addr(addr, &packet[8]);
692                     log_info("LE Connection_complete (status=%u) %s\n", packet[3], bd_addr_to_str(addr));
693                     // LE connections are auto-accepted, so just create a connection if there isn't one already
694                     conn = connection_for_address(addr);
695                     if (packet[3]){
696                         if (conn){
697                             // outgoing connection failed, remove entry
698                             linked_list_remove(&hci_stack.connections, (linked_item_t *) conn);
699                             btstack_memory_hci_connection_free( conn );
700 
701                         }
702                         // if authentication error, also delete link key
703                         if (packet[3] == 0x05) {
704                             hci_drop_link_key_for_bd_addr(&addr);
705                         }
706                         break;
707                     }
708                     if (!conn){
709                         conn = create_connection_for_addr(addr);
710                     }
711                     if (!conn){
712                         // no memory
713                         break;
714                     }
715 
716                     conn->state = OPEN;
717                     conn->con_handle = READ_BT_16(packet, 4);
718 
719                     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
720 
721                     // restart timer
722                     // run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
723                     // run_loop_add_timer(&conn->timeout);
724 
725                     log_info("New connection: handle %u, %s\n", conn->con_handle, bd_addr_to_str(conn->address));
726 
727                     hci_emit_nr_connections_changed();
728                     break;
729 
730             // printf("LE buffer size: %u, count %u\n", READ_BT_16(packet,6), packet[8]);
731 
732                 default:
733                     break;
734             }
735             break;
736 #endif
737 
738         default:
739             break;
740     }
741 
742     // handle BT initialization
743     if (hci_stack.state == HCI_STATE_INITIALIZING){
744         if (hci_stack.substate % 2){
745             // odd: waiting for event
746             if (packet[0] == HCI_EVENT_COMMAND_COMPLETE || packet[0] == HCI_EVENT_COMMAND_STATUS){
747                 // wait for explicit COMMAND COMPLETE on RESET
748                 if (hci_stack.substate > 1 || COMMAND_COMPLETE_EVENT(packet, hci_reset)) {
749                     hci_stack.substate++;
750                 }
751             }
752         }
753     }
754 
755     // help with BT sleep
756     if (hci_stack.state == HCI_STATE_FALLING_ASLEEP
757         && hci_stack.substate == 1
758         && COMMAND_COMPLETE_EVENT(packet, hci_write_scan_enable)){
759         hci_stack.substate++;
760     }
761 
762     hci_stack.packet_handler(HCI_EVENT_PACKET, packet, size);
763 
764 	// execute main loop
765 	hci_run();
766 }
767 
768 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
769     switch (packet_type) {
770         case HCI_EVENT_PACKET:
771             event_handler(packet, size);
772             break;
773         case HCI_ACL_DATA_PACKET:
774             acl_handler(packet, size);
775             break;
776         default:
777             break;
778     }
779 }
780 
781 /** Register HCI packet handlers */
782 void hci_register_packet_handler(void (*handler)(uint8_t packet_type, uint8_t *packet, uint16_t size)){
783     hci_stack.packet_handler = handler;
784 }
785 
786 void hci_init(hci_transport_t *transport, void *config, bt_control_t *control, remote_device_db_t const* remote_device_db){
787 
788     // reference to use transport layer implementation
789     hci_stack.hci_transport = transport;
790 
791     // references to used control implementation
792     hci_stack.control = control;
793 
794     // reference to used config
795     hci_stack.config = config;
796 
797     // no connections yet
798     hci_stack.connections = NULL;
799     hci_stack.discoverable = 0;
800     hci_stack.connectable = 0;
801 
802     // no pending cmds
803     hci_stack.decline_reason = 0;
804     hci_stack.new_scan_enable_value = 0xff;
805 
806     // higher level handler
807     hci_stack.packet_handler = dummy_handler;
808 
809     // store and open remote device db
810     hci_stack.remote_device_db = remote_device_db;
811     if (hci_stack.remote_device_db) {
812         hci_stack.remote_device_db->open();
813     }
814 
815     // max acl payload size defined in config.h
816     hci_stack.acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
817 
818     // register packet handlers with transport
819     transport->register_packet_handler(&packet_handler);
820 
821     hci_stack.state = HCI_STATE_OFF;
822 
823     // class of device
824     hci_stack.class_of_device = 0x007a020c; // Smartphone
825 
826     // Secure Simple Pairing default: enable, no I/O capabilities, auto accept
827     hci_stack.ssp_enable = 1;
828     hci_stack.ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
829     hci_stack.ssp_authentication_requirement = 0;
830     hci_stack.ssp_auto_accept = 1;
831 }
832 
833 void hci_close(){
834     // close remote device db
835     if (hci_stack.remote_device_db) {
836         hci_stack.remote_device_db->close();
837     }
838     while (hci_stack.connections) {
839         hci_shutdown_connection((hci_connection_t *) hci_stack.connections);
840 }
841     hci_power_control(HCI_POWER_OFF);
842 }
843 
844 // State-Module-Driver overview
845 // state                    module  low-level
846 // HCI_STATE_OFF             off      close
847 // HCI_STATE_INITIALIZING,   on       open
848 // HCI_STATE_WORKING,        on       open
849 // HCI_STATE_HALTING,        on       open
850 // HCI_STATE_SLEEPING,    off/sleep   close
851 // HCI_STATE_FALLING_ASLEEP  on       open
852 
853 static int hci_power_control_on(void){
854 
855     // power on
856     int err = 0;
857     if (hci_stack.control && hci_stack.control->on){
858         err = (*hci_stack.control->on)(hci_stack.config);
859     }
860     if (err){
861         log_error( "POWER_ON failed\n");
862         hci_emit_hci_open_failed();
863         return err;
864     }
865 
866     // open low-level device
867     err = hci_stack.hci_transport->open(hci_stack.config);
868     if (err){
869         log_error( "HCI_INIT failed, turning Bluetooth off again\n");
870         if (hci_stack.control && hci_stack.control->off){
871             (*hci_stack.control->off)(hci_stack.config);
872         }
873         hci_emit_hci_open_failed();
874         return err;
875     }
876     return 0;
877 }
878 
879 static void hci_power_control_off(void){
880 
881     log_info("hci_power_control_off\n");
882 
883     // close low-level device
884     hci_stack.hci_transport->close(hci_stack.config);
885 
886     log_info("hci_power_control_off - hci_transport closed\n");
887 
888     // power off
889     if (hci_stack.control && hci_stack.control->off){
890         (*hci_stack.control->off)(hci_stack.config);
891     }
892 
893     log_info("hci_power_control_off - control closed\n");
894 
895     hci_stack.state = HCI_STATE_OFF;
896 }
897 
898 static void hci_power_control_sleep(void){
899 
900     log_info("hci_power_control_sleep\n");
901 
902 #if 0
903     // don't close serial port during sleep
904 
905     // close low-level device
906     hci_stack.hci_transport->close(hci_stack.config);
907 #endif
908 
909     // sleep mode
910     if (hci_stack.control && hci_stack.control->sleep){
911         (*hci_stack.control->sleep)(hci_stack.config);
912     }
913 
914     hci_stack.state = HCI_STATE_SLEEPING;
915 }
916 
917 static int hci_power_control_wake(void){
918 
919     log_info("hci_power_control_wake\n");
920 
921     // wake on
922     if (hci_stack.control && hci_stack.control->wake){
923         (*hci_stack.control->wake)(hci_stack.config);
924     }
925 
926 #if 0
927     // open low-level device
928     int err = hci_stack.hci_transport->open(hci_stack.config);
929     if (err){
930         log_error( "HCI_INIT failed, turning Bluetooth off again\n");
931         if (hci_stack.control && hci_stack.control->off){
932             (*hci_stack.control->off)(hci_stack.config);
933         }
934         hci_emit_hci_open_failed();
935         return err;
936     }
937 #endif
938 
939     return 0;
940 }
941 
942 
943 int hci_power_control(HCI_POWER_MODE power_mode){
944 
945     log_info("hci_power_control: %u, current mode %u\n", power_mode, hci_stack.state);
946 
947     int err = 0;
948     switch (hci_stack.state){
949 
950         case HCI_STATE_OFF:
951             switch (power_mode){
952                 case HCI_POWER_ON:
953                     err = hci_power_control_on();
954                     if (err) return err;
955                     // set up state machine
956                     hci_stack.num_cmd_packets = 1; // assume that one cmd can be sent
957                     hci_stack.state = HCI_STATE_INITIALIZING;
958                     hci_stack.substate = 0;
959                     break;
960                 case HCI_POWER_OFF:
961                     // do nothing
962                     break;
963                 case HCI_POWER_SLEEP:
964                     // do nothing (with SLEEP == OFF)
965                     break;
966             }
967             break;
968 
969         case HCI_STATE_INITIALIZING:
970             switch (power_mode){
971                 case HCI_POWER_ON:
972                     // do nothing
973                     break;
974                 case HCI_POWER_OFF:
975                     // no connections yet, just turn it off
976                     hci_power_control_off();
977                     break;
978                 case HCI_POWER_SLEEP:
979                     // no connections yet, just turn it off
980                     hci_power_control_sleep();
981                     break;
982             }
983             break;
984 
985         case HCI_STATE_WORKING:
986             switch (power_mode){
987                 case HCI_POWER_ON:
988                     // do nothing
989                     break;
990                 case HCI_POWER_OFF:
991                     // see hci_run
992                     hci_stack.state = HCI_STATE_HALTING;
993                     break;
994                 case HCI_POWER_SLEEP:
995                     // see hci_run
996                     hci_stack.state = HCI_STATE_FALLING_ASLEEP;
997                     hci_stack.substate = 0;
998                     break;
999             }
1000             break;
1001 
1002         case HCI_STATE_HALTING:
1003             switch (power_mode){
1004                 case HCI_POWER_ON:
1005                     // set up state machine
1006                     hci_stack.state = HCI_STATE_INITIALIZING;
1007                     hci_stack.substate = 0;
1008                     break;
1009                 case HCI_POWER_OFF:
1010                     // do nothing
1011                     break;
1012                 case HCI_POWER_SLEEP:
1013                     // see hci_run
1014                     hci_stack.state = HCI_STATE_FALLING_ASLEEP;
1015                     hci_stack.substate = 0;
1016                     break;
1017             }
1018             break;
1019 
1020         case HCI_STATE_FALLING_ASLEEP:
1021             switch (power_mode){
1022                 case HCI_POWER_ON:
1023 
1024 #if defined(USE_POWERMANAGEMENT) && defined(USE_BLUETOOL)
1025                     // nothing to do, if H4 supports power management
1026                     if (bt_control_iphone_power_management_enabled()){
1027                         hci_stack.state = HCI_STATE_INITIALIZING;
1028                         hci_stack.substate = HCI_INTIALIZING_SUBSTATE_AFTER_SLEEP;
1029                         break;
1030                     }
1031 #endif
1032                     // set up state machine
1033                     hci_stack.num_cmd_packets = 1; // assume that one cmd can be sent
1034                     hci_stack.state = HCI_STATE_INITIALIZING;
1035                     hci_stack.substate = 0;
1036                     break;
1037                 case HCI_POWER_OFF:
1038                     // see hci_run
1039                     hci_stack.state = HCI_STATE_HALTING;
1040                     break;
1041                 case HCI_POWER_SLEEP:
1042                     // do nothing
1043                     break;
1044             }
1045             break;
1046 
1047         case HCI_STATE_SLEEPING:
1048             switch (power_mode){
1049                 case HCI_POWER_ON:
1050 
1051 #if defined(USE_POWERMANAGEMENT) && defined(USE_BLUETOOL)
1052                     // nothing to do, if H4 supports power management
1053                     if (bt_control_iphone_power_management_enabled()){
1054                         hci_stack.state = HCI_STATE_INITIALIZING;
1055                         hci_stack.substate = HCI_INTIALIZING_SUBSTATE_AFTER_SLEEP;
1056                         hci_update_scan_enable();
1057                         break;
1058                     }
1059 #endif
1060                     err = hci_power_control_wake();
1061                     if (err) return err;
1062                     // set up state machine
1063                     hci_stack.num_cmd_packets = 1; // assume that one cmd can be sent
1064                     hci_stack.state = HCI_STATE_INITIALIZING;
1065                     hci_stack.substate = 0;
1066                     break;
1067                 case HCI_POWER_OFF:
1068                     hci_stack.state = HCI_STATE_HALTING;
1069                     break;
1070                 case HCI_POWER_SLEEP:
1071                     // do nothing
1072                     break;
1073             }
1074             break;
1075     }
1076 
1077     // create internal event
1078 	hci_emit_state();
1079 
1080 	// trigger next/first action
1081 	hci_run();
1082 
1083     return 0;
1084 }
1085 
1086 static void hci_update_scan_enable(void){
1087     // 2 = page scan, 1 = inq scan
1088     hci_stack.new_scan_enable_value  = hci_stack.connectable << 1 | hci_stack.discoverable;
1089     hci_run();
1090 }
1091 
1092 void hci_discoverable_control(uint8_t enable){
1093     if (enable) enable = 1; // normalize argument
1094 
1095     if (hci_stack.discoverable == enable){
1096         hci_emit_discoverable_enabled(hci_stack.discoverable);
1097         return;
1098     }
1099 
1100     hci_stack.discoverable = enable;
1101     hci_update_scan_enable();
1102 }
1103 
1104 void hci_connectable_control(uint8_t enable){
1105     if (enable) enable = 1; // normalize argument
1106 
1107     // don't emit event
1108     if (hci_stack.connectable == enable) return;
1109 
1110     hci_stack.connectable = enable;
1111     hci_update_scan_enable();
1112 }
1113 
1114 bd_addr_t * hci_local_bd_addr(void){
1115     return &hci_stack.local_bd_addr;
1116 }
1117 
1118 void hci_run(){
1119 
1120     hci_connection_t * connection;
1121     linked_item_t * it;
1122 
1123     if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) return;
1124 
1125     // global/non-connection oriented commands
1126 
1127     // decline incoming connections
1128     if (hci_stack.decline_reason){
1129         uint8_t reason = hci_stack.decline_reason;
1130         hci_stack.decline_reason = 0;
1131         hci_send_cmd(&hci_reject_connection_request, hci_stack.decline_addr, reason);
1132         return;
1133     }
1134 
1135     // send scan enable
1136     if (hci_stack.state == HCI_STATE_WORKING && hci_stack.new_scan_enable_value != 0xff && hci_classic_supported()){
1137         hci_send_cmd(&hci_write_scan_enable, hci_stack.new_scan_enable_value);
1138         hci_stack.new_scan_enable_value = 0xff;
1139         return;
1140     }
1141 
1142     // send pending HCI commands
1143     for (it = (linked_item_t *) hci_stack.connections; it ; it = it->next){
1144 
1145         connection = (hci_connection_t *) it;
1146 
1147         if (connection->state == RECEIVED_CONNECTION_REQUEST){
1148             log_info("sending hci_accept_connection_request\n");
1149             hci_send_cmd(&hci_accept_connection_request, connection->address, 1);
1150             connection->state = ACCEPTED_CONNECTION_REQUEST;
1151             return;
1152         }
1153 
1154         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
1155             link_key_t link_key;
1156             log_info("responding to link key request\n");
1157             if ( hci_stack.remote_device_db->get_link_key( &connection->address, &link_key)){
1158                hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
1159             } else {
1160                hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
1161             }
1162             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
1163             return;
1164         }
1165 
1166         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
1167             hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack.ssp_io_capability, NULL, hci_stack.ssp_authentication_requirement);
1168             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
1169             return;
1170         }
1171 
1172         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
1173             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
1174             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
1175             return;
1176         }
1177 
1178         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
1179             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
1180             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
1181             return;
1182         }
1183     }
1184 
1185     switch (hci_stack.state){
1186         case HCI_STATE_INITIALIZING:
1187             // log_info("hci_init: substate %u\n", hci_stack.substate);
1188             if (hci_stack.substate % 2) {
1189                 // odd: waiting for command completion
1190                 return;
1191             }
1192             switch (hci_stack.substate >> 1){
1193                 case 0: // RESET
1194                     hci_send_cmd(&hci_reset);
1195 
1196                     if (hci_stack.config == 0 || ((hci_uart_config_t *)hci_stack.config)->baudrate_main == 0){
1197                         // skip baud change
1198                         hci_stack.substate = 4; // >> 1 = 2
1199                     }
1200                     break;
1201                 case 1: // SEND BAUD CHANGE
1202                     hci_stack.control->baudrate_cmd(hci_stack.config, ((hci_uart_config_t *)hci_stack.config)->baudrate_main, hci_stack.hci_packet_buffer);
1203                     hci_send_cmd_packet(hci_stack.hci_packet_buffer, 3 + hci_stack.hci_packet_buffer[2]);
1204                     break;
1205                 case 2: // LOCAL BAUD CHANGE
1206                     hci_stack.hci_transport->set_baudrate(((hci_uart_config_t *)hci_stack.config)->baudrate_main);
1207                     hci_stack.substate += 2;
1208                     // break missing here for fall through
1209 
1210                 case 3:
1211                     // Custom initialization
1212                     if (hci_stack.control && hci_stack.control->next_cmd){
1213                         int valid_cmd = (*hci_stack.control->next_cmd)(hci_stack.config, hci_stack.hci_packet_buffer);
1214                         if (valid_cmd){
1215                             int size = 3 + hci_stack.hci_packet_buffer[2];
1216                             hci_stack.hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack.hci_packet_buffer, size);
1217                             hci_stack.substate = 4; // more init commands
1218                             break;
1219                         }
1220                         log_info("hci_run: init script done\n\r");
1221                     }
1222                     // otherwise continue
1223 					hci_send_cmd(&hci_read_bd_addr);
1224 					break;
1225 				case 4:
1226 					hci_send_cmd(&hci_read_buffer_size);
1227 					break;
1228                 case 5:
1229                     hci_send_cmd(&hci_read_local_supported_features);
1230                     break;
1231                 case 6:
1232                     if (hci_le_supported()){
1233                         hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x3FFFFFFF);
1234                     } else {
1235                         // Kensington Bluetoot 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1236                         hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x1FFFFFFF);
1237                     }
1238 
1239                     // skip Classic init commands for LE only chipsets
1240                     if (!hci_classic_supported()){
1241                         if (hci_le_supported()){
1242                             hci_stack.substate = 11 << 1;    // skip all classic command
1243                         } else {
1244                             log_error("Neither BR/EDR nor LE supported");
1245                             hci_stack.substate = 13 << 1;    // skip all
1246                         }
1247                     }
1248                     break;
1249                 case 7:
1250                     if (hci_ssp_supported()){
1251                         hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack.ssp_enable);
1252                         break;
1253                     }
1254                     hci_stack.substate += 2;
1255                     // break missing here for fall through
1256 
1257                 case 8:
1258                     // ca. 15 sec
1259                     hci_send_cmd(&hci_write_page_timeout, 0x6000);
1260                     break;
1261                 case 9:
1262                     hci_send_cmd(&hci_write_class_of_device, hci_stack.class_of_device);
1263                     break;
1264                 case 10:
1265                     if (hci_stack.local_name){
1266                         hci_send_cmd(&hci_write_local_name, hci_stack.local_name);
1267                     } else {
1268                         char hostname[30];
1269 #ifdef EMBEDDED
1270                         // BTstack-11:22:33:44:55:66
1271                         strcpy(hostname, "BTstack ");
1272                         strcat(hostname, bd_addr_to_str(hci_stack.local_bd_addr));
1273                         printf("---> Name %s\n", hostname);
1274 #else
1275                         // hostname for POSIX systems
1276                         gethostname(hostname, 30);
1277                         hostname[29] = '\0';
1278 #endif
1279                         hci_send_cmd(&hci_write_local_name, hostname);
1280                     }
1281                     break;
1282                 case 11:
1283 					hci_send_cmd(&hci_write_scan_enable, (hci_stack.connectable << 1) | hci_stack.discoverable); // page scan
1284                     if (!hci_le_supported()){
1285                         // SKIP LE init for Classic only configuration
1286                         hci_stack.substate = 13 << 1;
1287                     }
1288 					break;
1289 
1290 #ifdef HAVE_BLE
1291                 // LE INIT
1292                 case 12:
1293                     hci_send_cmd(&hci_le_read_buffer_size);
1294                     break;
1295                 case 13:
1296                     // LE Supported Host = 1, Simultaneous Host = 0
1297                     hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1298                     break;
1299 #endif
1300 
1301                 // DONE
1302                 case 14:
1303                     // done.
1304                     hci_stack.state = HCI_STATE_WORKING;
1305                     hci_emit_state();
1306                     break;
1307                 default:
1308                     break;
1309             }
1310             hci_stack.substate++;
1311             break;
1312 
1313         case HCI_STATE_HALTING:
1314 
1315             log_info("HCI_STATE_HALTING\n");
1316             // close all open connections
1317             connection =  (hci_connection_t *) hci_stack.connections;
1318             if (connection){
1319 
1320                 // send disconnect
1321                 if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) return;
1322 
1323                 log_info("HCI_STATE_HALTING, connection %p, handle %u\n", connection, (uint16_t)connection->con_handle);
1324                 hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // remote closed connection
1325 
1326                 // send disconnected event right away - causes higher layer connections to get closed, too.
1327                 hci_shutdown_connection(connection);
1328                 return;
1329             }
1330             log_info("HCI_STATE_HALTING, calling off\n");
1331 
1332             // switch mode
1333             hci_power_control_off();
1334 
1335             log_info("HCI_STATE_HALTING, emitting state\n");
1336             hci_emit_state();
1337             log_info("HCI_STATE_HALTING, done\n");
1338             break;
1339 
1340         case HCI_STATE_FALLING_ASLEEP:
1341             switch(hci_stack.substate) {
1342                 case 0:
1343                     log_info("HCI_STATE_FALLING_ASLEEP\n");
1344                     // close all open connections
1345                     connection =  (hci_connection_t *) hci_stack.connections;
1346 
1347 #if defined(USE_POWERMANAGEMENT) && defined(USE_BLUETOOL)
1348                     // don't close connections, if H4 supports power management
1349                     if (bt_control_iphone_power_management_enabled()){
1350                         connection = NULL;
1351                     }
1352 #endif
1353                     if (connection){
1354 
1355                         // send disconnect
1356                         if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) return;
1357 
1358                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u\n", connection, (uint16_t)connection->con_handle);
1359                         hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // remote closed connection
1360 
1361                         // send disconnected event right away - causes higher layer connections to get closed, too.
1362                         hci_shutdown_connection(connection);
1363                         return;
1364                     }
1365 
1366                     if (hci_classic_supported()){
1367                         // disable page and inquiry scan
1368                         if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) return;
1369 
1370                         log_info("HCI_STATE_HALTING, disabling inq scans\n");
1371                         hci_send_cmd(&hci_write_scan_enable, hci_stack.connectable << 1); // drop inquiry scan but keep page scan
1372 
1373                         // continue in next sub state
1374                         hci_stack.substate++;
1375                         break;
1376                     }
1377                     // fall through for ble-only chips
1378 
1379                 case 2:
1380                     log_info("HCI_STATE_HALTING, calling sleep\n");
1381 #if defined(USE_POWERMANAGEMENT) && defined(USE_BLUETOOL)
1382                     // don't actually go to sleep, if H4 supports power management
1383                     if (bt_control_iphone_power_management_enabled()){
1384                         // SLEEP MODE reached
1385                         hci_stack.state = HCI_STATE_SLEEPING;
1386                         hci_emit_state();
1387                         break;
1388                     }
1389 #endif
1390                     // switch mode
1391                     hci_power_control_sleep();  // changes hci_stack.state to SLEEP
1392                     hci_emit_state();
1393                     break;
1394 
1395                 default:
1396                     break;
1397             }
1398             break;
1399 
1400         default:
1401             break;
1402     }
1403 }
1404 
1405 int hci_send_cmd_packet(uint8_t *packet, int size){
1406     bd_addr_t addr;
1407     hci_connection_t * conn;
1408     // house-keeping
1409 
1410     // create_connection?
1411     if (IS_COMMAND(packet, hci_create_connection)){
1412         bt_flip_addr(addr, &packet[3]);
1413         log_info("Create_connection to %s\n", bd_addr_to_str(addr));
1414         conn = connection_for_address(addr);
1415         if (conn) {
1416             // if connection exists
1417             if (conn->state == OPEN) {
1418                 // and OPEN, emit connection complete command
1419                 hci_emit_connection_complete(conn, 0);
1420             }
1421             //    otherwise, just ignore as it is already in the open process
1422             return 0; // don't sent packet to controller
1423 
1424         }
1425         // create connection struct and register, state = SENT_CREATE_CONNECTION
1426         conn = create_connection_for_addr(addr);
1427         if (!conn){
1428             // notify client that alloc failed
1429             hci_emit_connection_complete(conn, BTSTACK_MEMORY_ALLOC_FAILED);
1430             return 0; // don't sent packet to controller
1431         }
1432         conn->state = SENT_CREATE_CONNECTION;
1433     }
1434 
1435     if (IS_COMMAND(packet, hci_link_key_request_reply)){
1436         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
1437     }
1438     if (IS_COMMAND(packet, hci_link_key_request_negative_reply)){
1439         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
1440     }
1441     if (IS_COMMAND(packet, hci_pin_code_request_reply)){
1442         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_PIN_CODE_REPLY);
1443     }
1444     if (IS_COMMAND(packet, hci_pin_code_request_negative_reply)){
1445         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_PIN_CODE_NEGATIVE_REPLY);
1446     }
1447 
1448     if (IS_COMMAND(packet, hci_delete_stored_link_key)){
1449         if (hci_stack.remote_device_db){
1450             bt_flip_addr(addr, &packet[3]);
1451             hci_stack.remote_device_db->delete_link_key(&addr);
1452         }
1453     }
1454 
1455     hci_stack.num_cmd_packets--;
1456     return hci_stack.hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
1457 }
1458 
1459 // Configure Secure Simple Pairing
1460 
1461 // enable will enable SSP during init
1462 void hci_ssp_set_enable(int enable){
1463     hci_stack.ssp_enable = enable;
1464 }
1465 
1466 // if set, BTstack will respond to io capability request using authentication requirement
1467 void hci_ssp_set_io_capability(int io_capability){
1468     hci_stack.ssp_io_capability = io_capability;
1469 }
1470 void hci_ssp_set_authentication_requirement(int authentication_requirement){
1471     hci_stack.ssp_authentication_requirement = authentication_requirement;
1472 }
1473 
1474 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
1475 void hci_ssp_set_auto_accept(int auto_accept){
1476     hci_stack.ssp_auto_accept = auto_accept;
1477 }
1478 
1479 /**
1480  * pre: numcmds >= 0 - it's allowed to send a command to the controller
1481  */
1482 int hci_send_cmd(const hci_cmd_t *cmd, ...){
1483     va_list argptr;
1484     va_start(argptr, cmd);
1485     uint16_t size = hci_create_cmd_internal(hci_stack.hci_packet_buffer, cmd, argptr);
1486     va_end(argptr);
1487     return hci_send_cmd_packet(hci_stack.hci_packet_buffer, size);
1488 }
1489 
1490 // Create various non-HCI events.
1491 // TODO: generalize, use table similar to hci_create_command
1492 
1493 void hci_emit_state(){
1494     log_info("BTSTACK_EVENT_STATE %u", hci_stack.state);
1495     uint8_t event[3];
1496     event[0] = BTSTACK_EVENT_STATE;
1497     event[1] = sizeof(event) - 2;
1498     event[2] = hci_stack.state;
1499     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1500     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1501 }
1502 
1503 void hci_emit_connection_complete(hci_connection_t *conn, uint8_t status){
1504     uint8_t event[13];
1505     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
1506     event[1] = sizeof(event) - 2;
1507     event[2] = status;
1508     bt_store_16(event, 3, conn->con_handle);
1509     bt_flip_addr(&event[5], conn->address);
1510     event[11] = 1; // ACL connection
1511     event[12] = 0; // encryption disabled
1512     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1513     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1514 }
1515 
1516 void hci_emit_disconnection_complete(uint16_t handle, uint8_t reason){
1517     uint8_t event[6];
1518     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
1519     event[1] = sizeof(event) - 2;
1520     event[2] = 0; // status = OK
1521     bt_store_16(event, 3, handle);
1522     event[5] = reason;
1523     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1524     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1525 }
1526 
1527 void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
1528     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
1529     uint8_t event[4];
1530     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
1531     event[1] = sizeof(event) - 2;
1532     bt_store_16(event, 2, conn->con_handle);
1533     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1534     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1535 }
1536 
1537 void hci_emit_nr_connections_changed(){
1538     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
1539     uint8_t event[3];
1540     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
1541     event[1] = sizeof(event) - 2;
1542     event[2] = nr_hci_connections();
1543     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1544     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1545 }
1546 
1547 void hci_emit_hci_open_failed(){
1548     log_info("BTSTACK_EVENT_POWERON_FAILED");
1549     uint8_t event[2];
1550     event[0] = BTSTACK_EVENT_POWERON_FAILED;
1551     event[1] = sizeof(event) - 2;
1552     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1553     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1554 }
1555 
1556 #ifndef EMBEDDED
1557 void hci_emit_btstack_version() {
1558     log_info("BTSTACK_EVENT_VERSION %u.%u", BTSTACK_MAJOR, BTSTACK_MINOR);
1559     uint8_t event[6];
1560     event[0] = BTSTACK_EVENT_VERSION;
1561     event[1] = sizeof(event) - 2;
1562     event[2] = BTSTACK_MAJOR;
1563     event[3] = BTSTACK_MINOR;
1564     bt_store_16(event, 4, BTSTACK_REVISION);
1565     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1566     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1567 }
1568 #endif
1569 
1570 void hci_emit_system_bluetooth_enabled(uint8_t enabled){
1571     log_info("BTSTACK_EVENT_SYSTEM_BLUETOOTH_ENABLED %u", enabled);
1572     uint8_t event[3];
1573     event[0] = BTSTACK_EVENT_SYSTEM_BLUETOOTH_ENABLED;
1574     event[1] = sizeof(event) - 2;
1575     event[2] = enabled;
1576     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1577     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1578 }
1579 
1580 void hci_emit_remote_name_cached(bd_addr_t *addr, device_name_t *name){
1581     uint8_t event[2+1+6+248+1]; // +1 for \0 in log_info
1582     event[0] = BTSTACK_EVENT_REMOTE_NAME_CACHED;
1583     event[1] = sizeof(event) - 2 - 1;
1584     event[2] = 0;   // just to be compatible with HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
1585     bt_flip_addr(&event[3], *addr);
1586     memcpy(&event[9], name, 248);
1587 
1588     event[9+248] = 0;   // assert \0 for log_info
1589     log_info("BTSTACK_EVENT_REMOTE_NAME_CACHED %s = '%s'", bd_addr_to_str(*addr), &event[9]);
1590 
1591     hci_dump_packet(HCI_EVENT_PACKET, 0, event, sizeof(event)-1);
1592     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event)-1);
1593 }
1594 
1595 void hci_emit_discoverable_enabled(uint8_t enabled){
1596     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
1597     uint8_t event[3];
1598     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
1599     event[1] = sizeof(event) - 2;
1600     event[2] = enabled;
1601     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1602     hci_stack.packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1603 }
1604